recommendations: a timing issue
So, I was originally planning to ask two professors if they would be willing to write letters of recommendation for me. And this request would really mean "will you write a letter of recommendation for me x4?" (That is, I am applying to 4 schools and each school requires 2 referees) So I thought that I would make it as streamlined as possible for them by dropping off a packet of info for each, and in this packet would be all the info they would need-- that means all the info they would need for all four schools.
But now I am starting to realize that certain deadlines are coming up very quickly, and certain other schools haven't even opened up their applications process for 2010 yet and won't be for months. So, do you think it is still ok to ask these professors to write letters for all 4 schools? It means, basically, they'll have to be doing this "project" for me four separate times over the course of several months, instead of (what I envisioned) doing it once and basically just altering it slightly for each program, sending them all off, and be done with it. I feel almost like i'd be imposing too much by asking them to do this. How do people generally deal with this issue of having many schools, all requiring several letters of recommendation?
I know nothing. Halp.
Thanks.