If you are sending pulses, the pulses will get further apart as you accelerate away and shorter as you slow down. This will cause your clocks to desynchronize and you’ll find that a different amount of time has passed for you than your own clock. This is called relativity. You can say that your flashing clock is The One True Clock and if everything in the universe agrees with you, then I suppose it’s true. But one persons clock won’t be flashing at the same speed as another ones. This includes earth where one season we will be moving away (slower) and another we will be getting closer (speeding up). That’s be pretty annoying.