Train from London to Edinburgh?

Hello reddit,

I am going to visit London, Edinburgh, and Dublin the last 2 weeks of March. I want to take a train from London to Edinburgh, but I am having trouble finding a direct train for the date I am looking for. I wanted to take the LNER train from King's Cross, but I am not seeing any direct trains on the date I am leaving London for Edinburgh, only one with 3 transfers. Avanti West Coast has direct trains to Edinburgh, but I have seen a ton of bad reviews about Avanti's trains, scheduling, and employees. Does LNER not operate direct trains on Saturdays? Should I change my trip itinerary to accommodate a direct LNER train on another date, would Avanti be a decent option, or should I just fly? I really want to take the train, but I don't want to change the dates and itinerary for my trip. I started booking flights and hotels for this trip in October, but the train schedules for /March just came out, so now I am lost as to what to do. My plan had been to take a direct LNER train so I could enjoy the scenery on the east coast. This is my first international trip, and my second vacation since 2001, and I am a little overwhelmed and lost right now. I have been waiting months to finalize my bookings and now see that the one day I want to take a direct train, there are none on the line I want to use. Am I just trying to book on LNER too early, or is there some issue they are having? I noticed that the 22nd seems to be the only date around the time I am traveling that LNER does not offer a direct train to Edinburgh. I have reached out to LNER, but so far I have not gotten a response from them.

My plan is to fly into LHR on March 18th, stay 4 nights at the Hilton London Hyde Park. Take a train to Edinburgh on the 22nd and stay there for 3 nights before flying to Dublin for 3 nights and heading back to the US. Are there any other options for getting to Edinburgh form London, or any advice on rearranging my itinerary for this trip? Thanks you for any advice you may be able to offer.