That's right it was overcast. The blue sky just stated to show towards the end of the roll. I need to try FP4+ again on a sunny day and maybe at box speed and start experimenting from there.
Because it was overcast you got away with shooting @ 200EI. in fact that probably increased the contrast slightly in your favor. If you read Ansel Adams - Thwe Negative that would be around N+1 using the Zone System.
The Negative is one of the best books on Film exposure and processing well worth buying a copy.