Although my experience wasn't exactly the same, it may help. about
4 weeks out from surgery (foley out since day 6), my urine flow started to be restricted. Over the next week until I saw the surgeon, it got less and less. The restriction seems to me near the exit end of the urethra and it caused a whole lot of back pressure in the penis (and lots of pain). I finally saw the doctor on a Thursday and he put me in surgery the next day.
It was a very simple and short procedure, to cut the stricture in the end of the urethra. I was only put out for about 30-45 minutes. I had a foley in for one day, but the surgeon told us how to remove it ourselves the next day.
Doesn't sound exactly like what you are experiencing, but I thought I would pass it on.