Have heard that Erdogan is sick.. Circles around his eyes might be an indicator.
He has a son, if the vacancy happens, not sure the son is well know enough to actually get elected. But, the percentage of Islamists in Turkey now is pretty large.
Lots of unrest in Turkey, Economy is a disaster, huge inflation. The Kemalists were recently suppressed again, a new election might tilt the power toward them. Before Erdogan, the Kemalists has control since the end of WWI.