The midfielder is down the pecking order in a crowded Celtic midfield corps and will move south of the border on a season-long loan.
Allan joined from Hibs at the beginning of last season, but found it difficult to break into the Celtic Park first-team with only three starts in 17 appearances across the campaign.
He had been heavily linked with a move to boyhood heroes Rangers, though Hibs were not prepared to sell to their Ladbrokes Championship rivals and accepted Celtic’s bid when it came.
He’ll now get the chance to star again under Stubbs, who initially brought the playmaker back to Scottish football at the beginning of the 2014-15 season.
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