I'd maybe reconsider the quarter tab of letro. They normally come as 2.5mg tabs, a quarter of one of those would probably be OK, however these are 5mg tabs and 1.25mg every 2 days seems a bit high.
I'd probably start very low and see how you find it, if you get regular bloods even better, you'll be able to really dial it in.
If you are comfortable and experienced with them then ignore this, just a suggestion is all this is bro.
I used 2.5mg letro tabs about 8 years ago for gyno cure, they are very strong and did the job, strange tho haven't had even a sensitive nip since and very rarely use any type of ai at all nowadays.

Enjoy your cycle,