$540 via promo credit when you add a new smartphone line with your own 4G/5G smartphone on postpaid Unlimited Plus plan between 5/18/23 - 5/31/23 & port-in req'd. Promo credit applied over 36 months; promo credits end if eligibility requirements are no longer met.
Should my operating system be upgraded beyond 5.1?
if it can, yes. its been tested, so update will only improve and extend its usability