If you can be interested in technical details of parliamentary procedure, rather than a sterile rehearsal of arguments for or against the ban, note that the bit of the Parliament Act allowing the Commons to put forward a small amendment (like the two-year delay here) has never yet been invoked. Exciting, no?
If I understand things correctly, the Commons can force the Lords to debate the amendment, but can't actually enact it without the Lords' co-operation (and all factions in the Lords are showing the co-operative instincts of a farrow of piglets about this bill). It's very unlikely actually to become law, though you can see why Labour's election strategists might want to try.
Delay in implementation
If I understand things correctly, the Commons can force the Lords to debate the amendment, but can't actually enact it without the Lords' co-operation (and all factions in the Lords are showing the co-operative instincts of a farrow of piglets about this bill). It's very unlikely actually to become law, though you can see why Labour's election strategists might want to try.
HTFB