Hi Chops, thank you for getting in touch about your mobile options. Sincerest apologies for the lack of communication to support you with alternative mobile options.
Massive thanks to Enlli for offering help and support with your query until we picked this up!
They are completely right, to get your PAC code you can text PAC and your date of birth (in DD/MM/YYYY format) to 65075.
If you would prefer to speak to the team to do this you can by calling 0345 6000 789 (or 789 from a Virgin Mobile handset).
If you do decide to go with O2 and would like to activate your VOLT benefits, you do this via the My O2 account under the More > Volt Benefits tab options.
If you would like any more information on VOLT you can find this here.
Please do let us know if there is anything further we can support you with!
All the best.