Don't give up yet!!
If you have to restrip to bare metal, lay down a good coat of epoxy primer. There are several pretty good ones out there now. I used Nason to begin with but it becomes so hard that it is difficult to work with. I found a small company, Southern Polyurethanes (SPI) that lays down nicely, is fairly easy to sand and protects the bare metal. Then, when you have more time, you can just scuff the epoxy with 180 or 220, do your filler work, then 2K and your final BC/CC. Nice thing about SPI, you give them a call and you talk to the owner, Barry - super customer service guy. They do have a web site. I've had to call him 3 times about my errors and when done, know exactly how to procede. If you epoxy first, then any time interruption doesn't cause grief and aggravation. You don't have to worry about any porous filler sucking up water, rusting and eventually 'popping'. I'm caught with cold weather and my car sits waiting for a 'balmy' 50deg day so I can do some more painting - and am not worried about rust.