I do both a late summer no fert compost and a pre fert compost in spring crazy idea huh but as of yet I have noticed no problems. I would however suggest you might not want to water the newly added compost for the rest of the season the cool damp nights will pack it down quite a bit and I dont think you want standing water this time of the year

a last step I do as well with the late season compost adding is to hand airate it after a week good luck on getting that warmer day
Sleep well you have done no harm

If you put your compost down as a mulch it will take time for the soil bacteria to work it into the soil so putting some down now will not stimulate new growth, but that compost will be there ready to feed your roses next spring when they start growing again.

Thanks for the advice,I had kinda hoped it would work that wy of not promoting growth until next spring.I'll see then if the roses jump!