Hello! This is actually no longer true. You will have the chance to meet all potential ROs of the series in book one.
As for locking choices… I am not a fan of it. Can you not flirt with Alain if you have done the same with Alessa? Can you flush under Vallen’s stare even if you’ve returned some of Hadrian’s attentions? Can you flirt with the fishwife? Tease the horse master?
I know I’ve said it before, and excuse me for being a broken record, but I really like, as a reader, when there are consequences for my actions. And I want those consequences to translate into text. Into narrative.
That doesn’t mean you will never enter a relationship, however. Quite the contrary. All romance options will have a point where you both decide to be together. To devote yourself to one another. Either in conversation, with some characters, or through gestures with others. There will be a point where, say, Alessa considers you with her. And the MC considers her with them.
With all the expectations and responsibilities that entails.
What I mean when I say that I won’t lock romance, is that even after that point, well… you have freedom. You can make decisions. I won’t lock those possibilities. You’ll just have to be prepared to deal with the consequences of your actions.
I’ll also use this opportunity to give a little progress update.
Writing has been going very well! Chapter 6 stands at 32k words, and so far, writing the second draft has been as enjoyable as the first.
This chapter has 4 big, major scenes. I managed to finish the first one this week and make a very decent head-start in the second. This second one, however, has two split versions. My goal is to either finish or be near finishing the first version of scene two by the end of next week. Fingers crossed! 
But one of the four giants is done, and it was also the one I was most nervous about. The beginning of chapters… those are always difficult. Plus, it dealt with someone I was itching to introduce for a long time. I want to do good by them, they are a character that has been with me for years.
Only time will tell if I succeeded, but I am happy with what I wrote. I suppose that, in the end, that’s all I can do.
I wish you all a lovely weekend! 