Any experiences switching from Xeljanz to Entyvio?

Hi there! Has anyone had experience switching from Xeljanz to Entyvio amidst remission? How did it go?

I was diagnosed with UC about 4 years ago. For three years, mesalamine worked for me. I had several minor flares when I reduced rectal formulations, but increasing them helped me get back to normal. Then I had a flare last autumn, which coincided with the beginning of my IVF treatment. It actually started slightly before the IVF, but it looks like the IVF-related medicines could do some harm as well. Anyway, I had to stop my transfer protocol because calprotectin level reached 316 and I had some discomfort, though no blood and 1-2 BM a day on average. I was prescribed an increased dosage of mesalamine, but I still had some discomfort. I could feel that there was still some inflammation; calprotectin levels were 70-80 at that time. My doctor, though, said the symptoms were more of IBS than IBD. Then I traveled and came down with some stomach infection. It didn't seem serious at first, but it got worse and worse. I was prescribed antibiotics, and then things went awfully.

I had to be hospitalized with a severe flare-up. Lots of pain, 6-8 BM with blood etc. IV prednisolone didn't work, I was diagnosed with steroid-refractory acute severe ulcerative colitis. As a rescue therapy, the doctor in the hospital suggested Xeljanz (Tofacitinib), because Infliximab is not available in my country. Xeljanz worked pretty fast, and I was then discharged home. My calprotectin level was 12 just one month after that horrible flare. The doctor then made a plan for me to reach a full remission on Xeljanz while tapering pred and then switch to Entyvio because I want to continue my IVF treatment, and Xeljanz is not compatible with that.

12 days ago, I stopped Xeljanz because my symptoms, fecal calprotectin level, and recto-sigmoidoscopy indicated remission. I'm scheduled to have my first Entyvio infusion next week. In the meantime, I take 2 g of oral mesalamine daily and a suppository three times a week. However, two days ago, I started feeling some worsening of the symptoms. No blood, 1 BM a day, but more urgency in the morning and more discomfort (minor spasms, some gas). I'm so anxious that this transition to Entyvio may end in a flare. Xeljanz worked perfectly, but I have a lot of pressure due to IVF plans (I'm 41 y.o., so time pressure is huge too).

I'd appreciate your stories if you've had a similar experience or have some thoughts on this. Thank you all. This is my first post here, though I found so much information and indirect support through reading the sub.