I'm so sorry to see that Linus is missing. He's a beautiful boy.
All of us will have a good idea of how you're feeling at this moment, and all of us will be hoping that some news will come to you, which will mean you can be reunited safely with Linus as soon as possible.
There have been a number of cases where missing cats have been reunited with their family, so don't give up hope.
If you haven't already done so, it would be a good idea to contact all of your local veterinary surgeries and give them a copy of your flyer, and to post on Facebook and any local community based forum such as Streetlife.