OPTION 1.
Without a second of hesitation.
Bias.
I am an old pilot so I can only look back with experience and not forward in hope. (Well, not as far as a flying career is concerned anyway.) But then I probably sound like a father figure which is not necessarily the best medium for advice.
Reasons.
You are obviously a very academic smart cookie and hard working too of course. So it can be assumed you will achieve your MSc within one year.
I think that there can be no doubt that a year spent on an MSc will far outweigh any differential in the synaptic age curve between 29 and 31.
It is also my opinion that a Master's degree in a serious subject, not basket weaving for example, would be of enormous advantage if the aviation business gets tough in the future. It confers almost unlimited street cred.
Besides that, I have a feeling that other opportunities with more limitless horizons might lie at the end of such a degree.
Good luck.