I think it is worth it to wait. Graduate school is a massive investment in time and resources, and will have a direct bearing on your future career opportunities. You don't want to compromise just to save a year. Spending 3 years on a program that you didn't want to go to in the first place is unwise to say the least.

That said - it is not impossible to prepare within a few months. A classmate of mine managed to finish his application within four months or so. However, he has had years of very interesting work experience outside architecture, a host of academic prizes from his undergraduate studies, and excellent standardized scores. All these informed the committee's decision to admit him, despite the relatively brief portfolio.

I applied under that timeline, but not to those schools. Got into a few top 20 programs though. It worked out in the end, but if you're dead set on these top schools I would give it an extra year if you can find a job and work on your portfolio. I was 29 when I started, so no rush.

I will throw my support behind the opposite tactic.

Four months is plenty if you're diligent.

I also respectfully disagree with monosierra. After your first few jobs, provided you keep moving forwards, nobody really gives much of a shit where you went to school, especially if you're licensed.

Even if they do, is that the type of practice you want to work with anyhow?

fuck. new york really warps my sense of time. i could have done my application three times over in 4 months.

You have plenty of time.

GRE scores are a minor factor for most programs - much less important than portfolio, references, and essay (in that order).  But GRE scores can be more important if your GPA is low.

Don't let a school's stated minimum GPA or GRE keep you from applying if you're below the threshold but close.  There are a few programs where the cutoff is firm and you'll likely be culled before your material even gets to the admission committee, but in most programs that is not the case.

Four months is plenty of time.  Consider that a lot of applicants are college students in their final year and they do a lot of their admissions prep during school breaks.  I get most requests for reference letters in the few days before Thanksgiving and Christmas breaks, and the application deadlines are usually only a few weeks later.  That's not ideal - you'll probably get stronger letters if you don't wait until the last minute - but it's not unusual. 

When I applied to grad schools I did all my essays and portfolios during the 3-week Christmas break from college - and that was back in the days before affordable digital printing so they were literally individual cut-and-paste projects. 

I'd like to hear your reasoning for that list of schools. First of all, it's way too many schools. Second, it's clear that you haven't done enough research into what you actually want out of an architecture program. These programs' strengths are all over the map, so it sounds like you're just prestige-hunting without any actual justification beyond wanting to go to a "good school."

That alone suggests you should take another year to actually figure out what (beyond a fancy name) you want to get out of graduate school.

I think placebeyondthesplines has got it spot on. It does seem like OP is not totally informed on the pedagogies on the schools listed. This is why I think it is better to go slow, research and visit the schools to understand their students and projects, and figure out proper what you want out of your degree.

About the prerequisites:  They're called prerequisites because you need to have them before you enroll.  Some of the schools you listed have strict policies on that - they will turn away admitted students who didn't successfully finish a calculus course before enrolling.  Don't assume that you can just omit these and finish them once you're admitted.

Even in the programs that do let you do that, it means you'd be adding a course to an already jam-packed first year curriculum.  Most of the programs you listed don't have any first-semester electives, so if you have to take calculus or physics on top of studio and three or four required core courses, you may be taking more than 20 credits and barely have time to breathe.  

Get all the pre-reqs over with before you start an M.Arch.

Typically any lacking prerequisites are taken the summer before enrolling, not on top of the first semester.

@kjdt

placebeyondthesplines is correct on that one.

That depends on the school, and the situation.

There are a few typical scenarios:

1. The student is enrolled in the course at the time that he applies for admission, but doesn't pass, or doesn't meet the threshold grade (usually a C).

2. The student takes the course in the summer before enrollment - either at the school at which he's planning to do the M.Arch, or at another institution - and doesn't pass, or doesn't meet the threshold.

3. The student blows off the pre-req and just shows up without it.

In any of those, it's at the discretion of the school how to handle that.  It can depend on what the missing course is, and which school.  Some do refuse to admit students in the fall if the pre-reqs haven't been met - in that case usually they will defer admission to the following year on the condition that the student successfully takes the courses.  More often the schools allow the student to start, with the condition that they take the missing courses in the fall semester, on top of the regular M.Arch core.

Try to do it all during the summer or the registrar will be on your case throughout your M.Arch. It is a pain to take some Physics exam during first year.

Totally. Why don't you try and see how it goes? If it doesn't work out, you can have another shot next year. Here's what I have done. You first tell your references/professors that you're applying and would love to have their recommendation. Then GRE. I prepared GRE for 6 weeks and had a good score. I'm good at exams but my English at the time was very basic. I studied GRE almost 15hours/day, except occasional readings on architecture books by professors at the schools I was applying to get a sense of how to shape my SOP. Then I worked on my portfolio and SOP simultaneously. For portfolio, I first collected all portfolios by those who are accepted by the schools I wanted. (archinect + issuu) Then I made a simple version of mine. I figured portfolio is less important for non-arch background applicants. After first two weeks, I had drafts and asked for opinions here and there and updated and asked again... Same process for SOP, but I think it took three weeks for the first draft, as I spent first week researching what I am specifically interested in architecture. If you have arch background, 1 year may not count much. But since you're changing your major, as I was, apply as early as possible and take a gap year after 2nd year at your grad school to gain enough work experience. For prequisites, you have 9 months to finish after you apply! It sounds intense, but remember the grad school will be even more intense...