It's been a while since I've dealt with it -- so don't quote me on the numbers.
As I recall, once they send you the COBRA notice, you have sixty days to decide. So, you can wait the 60 days, see if anything happened that warrants coverage.
Also, as I recall, your pre-existings must be covered under your new plan so long as you haven't suffered a lapse of more than 63 days in coverage.
So, if nothing happens during the 60 days before you elect coverage, go ahead and pay the first month. Then once your other coverage kicks in, just don't pay any further.
Obviously, if something happens during the 60 days that requires continuing coverage during months 2 and 3, then you should pay the COBRA premiums for those months to make sure those procedures are covered.
This is not legal advice. Go see an ERISA attorney before you do anything.
This post was edited on 2/12 at 7:54 am