Agreed with the above comments; it's nice to see Remus finally grow a spine after DH. I've felt that he was in the process of developing one during the events of DH, and his death stopped the process prematurely. Which sucked for canon!Remus, but opened up lots of possibilities for Remus in fic. Nice to see someone taking advantage of that.
However, I think my favorite part is this: "Right." Severus broke the seal with reluctance. He recognized Minerva's handwriting on the envelope, and he hoped she wasn't writing to censure them. Ignoring the icy apprehension clenching his stomach, he unfolded the letter and read swiftly -- and his lips quirked in something close to a smile. "It's from Minerva. She says it's about bloody time." -- Great image, and completely hilarious. Nice.