In House of Commons Procedure and Practice, third edition, 2017, page 550, under the heading “Motions to Adjourn the Debate”, the second paragraph reads:
A motion to adjourn the debate is in order when moved by a Member who has been recognized by the Speaker to take part in debate on a question before the House. It may not be moved during Routine Proceedings, except during debate on motions moved under the rubric “Motions”. The mover of the motion being debated may not move to adjourn the debate since this would involve moving two motions simultaneously. In addition, the restrictions which apply to motions to adjourn the House also apply to motions to adjourn the debate.