As of this evening, Tiffin Wallah is closed. There's a Health Dept yellow sticker in the window, and a handwritten note dated the 11th, saying that they're closed for repairs, and will reopen in 10 days from that date.
Continuing around the block, I found that Pongal has been taken over by R Israel Meir Steinberg. So much for that. So I ended up at Madras Mahal instead.