Q. The minhag in our shul is that during selichos days, the one who says selichos also davens for the amud, An ovel has been davening for a while by us, and has a chazoko (established rights) to the amud, but he is unable to say selichos. What has priority, the chazakah of the ovel or the minhag of the shul?
A. Horav Shlomo Miller Shlit’a quoted the minhag of the Toronto Kollel and other Ashkenazi institutions were avelim don’t daven shacharis during selichos.
If the minhag of your shul is that the one who recites selichos also davens for the amud, then it takes precedence and priority and the ovel does not daven shacharis by the omud during those days. However another ovel who is able to recite selichos can then take over.
Rabbi A. Bartfeld as advised by Horav Shlomo Miller and Horav Aharon Miller Shlit’a