Princess Kate is at last making her first public appearance in months, at Saturday’s Trooping the Colour in London—but that doesn’t mean royal watchers should expect her to return to full-time public duties just yet.

The Princess of Wales broke her silence today with a rare personal update on her cancer recovery and treatment process. In the frank letter, Kate said she is “making good progress,” but that “there are good days and bad days.”

“On those bad days you feel weak, tired, and you have to give in to your body resting,” she wrote in a letter released by Kensington Palace. “But on the good days, when you feel stronger, you want to make the most of feeling well.”

She continued, “My treatment is ongoing and will be for a few more months. On the days I feel well enough, it is a joy to engage with school life, spend personal time on the things that give me energy and positivity, as well as starting to do a little work from home.”

While she expressed her excitement over joining other members of the royal family at tomorrow’s annual summer celebration the British monarch’s birthday, she also noted: “I am not out of the woods yet. I am learning how to be patient, especially with uncertainty. Taking each day as it comes, listening to my body, and allowing myself to take this much-needed time to heal.”

The princess’s letter comes amid increased speculation over her whereabouts and health. Kate last made an official public appearance on December 25, when she joined the rest of the family in the traditional walk to Christmas morning service on the royals’ Sandringham estate. She has abstained from public duties since then, after undergoing an abdominal surgery in January. In March, she shocked the world with the announcement of her cancer diagnosis, though she refrained from specifying what type of cancer she has.

A royal insider previously talked to Bazaar about Kate’s return-to-work status. “There is no information about Kate’s ‘return’ because the focus at this moment in time is 100 percent on her health—to suggest she won’t return to her role is unfair and untrue,” the source said. “Conversations of that nature are just not being had. When the time is right, she will resume her work.”

You can read the letter Kate released today in full below.

“I have been blown away by all the kind messages of support and encouragement over the last couple of months. It really has made the world of difference to William and me and has helped us both through some of the harder times.

I am making good progress, but as anyone going through chemotherapy will know, there are good days and bad days. On those bad days you feel weak, tired, and you have to give in to your body resting. But on the good days, when you feel stronger, you want to make the most of feeling well.

My treatment is ongoing and will be for a few more months. On the days I feel well enough, it is a joy to engage with school life, spend personal time on the things that give me energy and positivity, as well as starting to do a little work from home.

I’m looking forward to attending the King’s Birthday Parade this weekend with my family and hope to join a few public engagements over the summer, but equally knowing I am not out of the woods yet.

I am learning how to be patient, especially with uncertainty. Taking each day as it comes, listening to my body, and allowing myself to take this much-needed time to heal.

Thank you so much for your continued understanding, and to all of you who have so bravely shared your stories with me.”