Have the same issue, haven't ever tried using a VPN so can't attest to that. Will add, have seen it also when fast traveling or going from one area planetside to another, or entering/leaving a lost sector, on occasion as well. But I've tested my ping/ packet loss/ speed/ etc to servers in Seattle when this is happening, and not seen any difference from then to when it is not happening. No packet loss, ping and speed remain consistent with low jitter. Been happening for around a year for me, and nothing I've done has helped.