Why is the noise gain of these opamps 500? I feel it should be 250

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I wanted to check the bandwidth of the first stage of an instrumentation amplifier configuration and this is the circuit:

https://preview.redd.it/vmzw878dxj971.png?width=1274&format=png&auto=webp&s=2e2ea2fd9d2a1ab14616bfe50e5c121676bc019f

Since, the noise gain of an opamp is (1 Rf/R1), for each of the op-amps the noise gain should be 250. The GBW of the opamps is 1MHz. This should give us a -3dB bandwidth for each of the opamps as 1MHz/250 ~ 4000Hz.

However, on simulation, I get the bandwidth as ~2KHz indicating a gain of 500. I don't get why. Yes the overall gain of first stage is 500, however, for the individual signals it should have been 250. Please tell me what I am missing here.

https://preview.redd.it/p0znsdkgxj971.png?width=1920&format=png&auto=webp&s=fa45ca7df8e6a4e84da4cd0eddbd3f8cd4168b82

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