Finally got around to applying for the 20+20gb deal.
Went in to the store, told the sales guy I wanted to cancel my current (10+10gb contract from the 8.ta days) and take out the new contract. Guy scanned in my ID, asked me a few authentication/security questions, confirmed all my details are still current, then went to fetch the router, WiFi repeater and SIM card from the store room and scanned them in. Didn't ask for Proof of Payment, Payslip, 3 Months Bank Statement etc. as it's already on the system. Ticked off a checklist of "Have you informed the customer of this?" questions, printed out my receipt, and 10 minutes later I was done.
Router was a Huawei B315s-936, came with power adapter, network cable, 2x external antennae, and a 2600mAh backup battery pack. Repeater was a netis E1+ 300Mbps Wireless N. Current speed below with it sitting on the floor next to my PC, will move it around later to get a proper signal.