Hi in a rather rainy July I walked from Fort William to Gerry Hostel on Cape Wrath Trail. Looking to do another section from Gerry Hostel to Ullapool at the end of April. Whilst I accept there are no guarantees what are condition like alone this line in April time.
I came through that stretch last year at the beginning of May. Weather was changeable but nothing too extreme. Midge was just starting to appear but not in the numbers to affect your mental state! No snow. That said though, you're right in there being no guarantees.....prepare for everything!