I definitely think they are hurting for subscriptions now, many guys are not on there for various reasons.

One being Covid 19.  Then with them allowing all the online only, pic/vid sellers, etc
Guys are not bothering to pay to be on there like before.  
Way too much b.s. with far to many not wanting to meet and scammers

SA better do something or they will be irrelevant within a year or two

This is not common, but they do this from time to time. I received the same offer, and a similar offer for their (older) sister site, WYP.  
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I've seen these before, perhaps once or twice a year.  
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Sugaring in many markets is somewhat cyclical. And Summer time may be a low volume period for new SD sign ups.  Perhaps because married men are doing family activities like family vacations or travel, have college age kids home while school is out, and use this time something other than work long hours.  
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IMO it's no different than the promotions they may offer SB's just before school starts in the Fall, or near the holiday season, or around Spring Break.  
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It's just marketing...  
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Life is good.
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The Cat

Everyone has a sale of some sort from time to time... this is the 2nd sale this year that I can think of.

I'm thinking of taking the plunge for 30 days.

When my membership comes near, I usually reach out one last time and include my hobby phone and another means of online communication (like Line if they're Asian), and a note that I may not be returning any time soon, so feel free to reach out to me.