When to repot Stlma Kelly Lea

[Fran20]

This was purchased in Oct,2019, described as blooming size. It came in a 2" pot. The tag lists 2 potting dates: 1/2016 and latest was 3/2017. My questions:
1) Should I repot into a 3" pot?
2) If yes, when should I repot--now or in Spring? I'm not too sure how to recognize new growth in this orchid.
3) Right now, it appears to be in a mix of fir bark and lava rock. I'm thinking of repotting in 1/4" size red lava rock. Would that be too much of a transition or should I stay with a bark-lava rock mix?
Thanks in advance for your advice.