Lowering Stats

Let's say I convert her training from dressage to something else, if I convert it again back to dressage will it lower her stats?? https://www.equiverse.com/horse.php?id=684695

The total number of stats,1508, will stay the same. However, any stats gained since birth will be divided between Agility and Intelligence, the Dressage stats. Check her Base Stats (next to Private Notes) and compare those non-specialty stats to her current non-specialty stats. If they are the same or a few off it would a waste money and credits. 
Hope that answers your question :)

Base stats: 
STR:17
SPD:21
AGI:458
INT:456
END:15
ALL:967

Current: 
STR: 43 +3
SPD: 41 +3
AGI: 694 +28
INT: 695 +28
END: 35 +3
ALL: 1508

So thats 66* stats  that can be move to Agility and Intelligence, 33 each. It's up to you if you feel spending 10k and 2 credits is worth it. Is she very important to your breeding program? If not don't double convert.
*The + 3s and 28s are tack bonuses and do not effect the total stat number e.g. 1508.

hmm...and she isn't my only one that I would have to convert :/ I think I'll do it to another horse that needs it more. Thanks!

You're welcome and good luck.