The High Luminosity Large Hadron Collider upgrade will increase the luminosity of the LHC by a factor of 10. Low gain avalanche detectors (LGADs) promise excellent timing resolution, which can mitigate the pileup associated with high luminosity. The most highly irradiated LGADs will be subject to 2.5*10^15 neq/cm^2 of hadron fluence during Run 4; their timing performance must tolerate this. Hamamatsu Photonics K.K. (HPK) and Fondazione Bruno Kessler (FBK) LGADs have been irradiated with 400 and 500 MeV protons respectively up to the Run 4 hadron equivalent fluence. Preliminary characterizations of the FBK gain layer depletion voltage and timing resolution are presented here.