Cashback tarting

bluep

Having not paid any line rental for SO long...and my husband's current deal coming to an end in April, will this work:

Currently on 02 pay monthly (want to ultimately stay on this network as it has best coverage in our area)

Get pac code

Take out Virgin 6 months pay monthly sim only deal (quidco cash back and free line rental for 6 months), then port back to 02 on a 12 months free deal or similar

OR

Take out Vodaphone pay monthly sim only deal (30 days contract, works out free for 3 months with cashback) and then port back to 02 etc...

Is there a minimum time between getting pac codes? Any networks this won't work between? We've always swopped networks every 12 months i.e. 02 port to Orange then after deal ends, port back to 02 for the next year etc...

He obviously wants to keep his number...

Thanks!