Just got an email from PlayStation with a code to claim 3 free months of Stan. The code acts as a free three month trial of the Stan Standard Plan for new customers/accounts, and as a free upgrade from Standard to Premium for current Stan customers (i.e. pay $14 for premium instead of $17).
"To say thanks for being a PlayStation Plus member and for electing to receive information about PlayStation products and services, you can now get 3 months of Stan on us. Already have Stan? Get an upgrade to Premium."
Terms and Conditions here, but basically:
1) You need to opt-in to information about PlayStation products and services, i.e. Go to https://account.sonyentertainmentnetwork.com > Notification Settings > Check "Yes, I would like to receive personalised info and offers related to Playstation and Sony.
2) You need to have an active 3 or 12 month PlayStation Plus membership, OR purchase a '3 Month Membership + 3 Months Stan' or '12 Month Membership + 3 Months Stan' from the PlayStation Store between 1 February 2019 and 28 February 2019 (deal doesn't seem to be live yet as of time of posting).
3) Cross your fingers you get an email from Sony with a code! For the last free Netflix promotion, I didn't receive an email but was able to live chat to PlayStation Support for a code but YMMV.
Also worth noting the promo won't work on accounts created via iTunes, and only one code can be redeemed per account. The subscription will automatically renew at the end of the three months unless cancelled.
Stan 3 Month Promo Code must be redeemed by 14 March 2019.
Does this offer apply for customers who have previously redeemed a free Stan trial?