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CCO pulsars are stable rotators with weak dipole B-fields and small spin-down rates. Old radio pulsars with similar spin parameters as CCOs are never seen to glitch. However comma the CCOs are much younger than their timing ages comma and we have discovered the first CCO glitch comma in our X-ray monitoring of 1E 1207.4-5209. CCOs are theorized to have strong comma buried crustal B-fields that will diffuse out in <1 Myr. The detection of a glitch therefore supports a recent conjecture that they could be triggered by the diffusion of these strong fields. We propose to continue timing 1E 1207.4-5209 comma to verify the unexpected large change in its post-glitch spin-down rate comma and to monitor the CCO in Puppis A for similar glitches. These observations may allow a first measurement of NS surface magnetic field growth