Is it possible to apply now to courses that do not require a letter of recommendation (LOR) and submit the LOR later when available in UK?

Yes, many UK and Irish universities let you submit your application before your letter of recommendation (LOR) is available, but policies vary by university and program.

Some universities will consider your application as long as most documents are submitted, while others require all references before processing. If a course specifically does not require an LOR, you can apply immediately. For courses that do require an LOR, some universities may allow you to add it later, but others may not assess your application until it is received.

Check each program’s requirements carefully.