Are there any tax benefits to transferring money from a checking account to an HSA before covering medical expenses?

My HSA is still below the annual contribution limit, and I have a medical bill to pay. The current balance in my HSA consists entirely of payroll deductions and employer contributions. Adjusting my payroll contribution to the HSA can take 30-60 days. Would there be any tax advantages to moving money from my checking account to the HSA before paying the medical bill?