TITLE: GCN CIRCULAR NUMBER: 18772 SUBJECT: GRB 151228A: Correction to GCN 18770 DATE: 15/12/30 13:49:06 GMT FROM: Kim Page at U.of Leicester K.L. Page (U. Leicester) reports on behalf of the Swift-XRT team: We apologise for the incomplete nature of GCN 18770, which was automatically sent out in error. The correct information is given below: We have analysed 2.2 ks of XRT data for GRB 151228A (Ukwatta et al., GCN Circ. 18731), from 178.6 to 196.5 ks after the BAT trigger. The data are entirely in Photon Counting (PC) mode. No X-ray source is detected in or near to the BAT refined error circle (Barthelmy et al., GCN Circ. 18754), to a 3-sigma upper limit of 7x10^-3 count s^-1, corresponding to an approximate observed flux of 3x10^-13 erg cm^-2 s^-1. This circular is an official product of the Swift-XRT team.