markalig

i have been getting clusters for 25 years - each period lasts 6-8 weeks - at first they returned every 8 months but in recent years i have had pain free period of 16 or 24 months. My last cluster period was Nov/Dec 2016. Then Nov/Dec 2018 most recently with clusters ending just before Christmas. Now in the 2nd week of January, only weeks later, i have started having clusters again on the other side of my head. The side has switched before between periods but i have never had a period come back only weeks after the previous. Has anyone experienced this and do you know why? Thanks for any help