BCB not yet confirming if Tamim will be the ODI team captain once he returns
Tamim wanted to have former ODI captain and member of Parliament Mashrafe as a mentor for the team and Jalal explained that the decision here needs to be made by the board.

The Bangladesh Cricket Board (BCB) cricket operations committee chairman Jalal Yunus spoke to the media about a multitude of things including the re-integration of Tamim Iqbal as the ODI captain along with bringing Mashrafe Mortaza in as a mentor on Tuesday.
"Let him return first as we are discussing [the matter of captaincy] with him. There is an issue regarding his fitness, and he said that, first, he will come back [to the country] and then discuss the matter," Jalal told the media after Bangladesh's seven-wicket victory in the final ODI against Afghanistan in Chattogram.
"Tamim is going to Dubai and from there he might fly to the UK on 25 or 26 July. He has appointments in two medical centers in the UK where the doctors will see him. He will update us about his condition from time to time. We will soon announce a primary squad of 25-26 members [for the upcoming Asia Cup] which is the reason we need to see his medical fitness and will then determine when he would join," Jalal added.
Tamim wanted to have former ODI captain and member of Parliament Mashrafe as a mentor for the team and Jalal explained that the decision here needs to be made by the board.
"Now the decision is the board's. Surely Mashrafe is a member of Parliament. He's a former captain. He has to come officially to us. He is a good captain and a good leader. We will talk when we come to the board," he concluded.