Hi
always easier to ask than seek through the mess that most web forums are.
So my migrain types are like this:
https://www.valvereplacement.org/threads/vision-disturbances-and-migraines.884398/post-884471
I find that neck mobility and posture are critical. I discovered this upon reflection when I changed from field work into desk work and had reason to go see an osteopath/chiropracter (after a bicycle accident). After seeing them for about a year I observed that I was not having anywhere near as many migraines as I once was. So I asked him about it and he said that yes, that was a known outcome but they (he) didn't promote that because it wasn't always certain. Probably they promote that now ...
I found that desk work promoted me to not have my neck mobile and my head looking in one direction for large amounts of time. Also that walks with a backpack were good but ONLY if I focused on my shoulder position and mobility.
Lastly I found that doing plain bench press (no, the machines do not elicit this) and starting the day with 2 or 3 sets of 30 reps with no more than 20kg on the bar also really helps to get the lower neck moving. Its important (in my workout) to move slowly and bring the bar (gently) to rest on my sternum and focus on my neck position and evaluate tightness. I then also do some shoulder shrugs where I do not lift up high but focus on drooping (stretching those trapezius shoulder muscles) and move the shoulder a little back on the down, then forward then up in an isosceles triangle. Usually 10kg in each hand.
If I start with that and then either don't do more or move on to more I have weeks without migraines. I haven't been able to go to a good chiro regularly for about a decade now and so those discoveries back in the 90's really helped me.
If I ignore all this I'll be back to having migraines a few times a week, sometimes 2 per day.
I hope that helps you