Temp change during "longer" fermentation

I can only ferment two batches at a controlled temp with my fermentation set up. Now that the weather is warming up, so is the basement. After two weeks in the controlled environment @ 64, I am going to the basement which is @ 68 for an additional 2 weeks. How is this going to effect my beer? Good, bad or meh.

Trying to keep the pipeline going, but don't want to mess up the quality of the beer, either.

You should be fine...storing as cool as possible is always best. After two weeks fermenting at 64F you are well on your way toward FG if not there already and that is the time when most flavors (and off flavors) are developed.

Maybe you can make some insulated boxes with ice water baths in the basement...once you hit FG you really can't get the beer too cold unless it freezes. Cold temps will help with cold stability and clarification.