Left and central panels: Gaia DR3 G-band light curves of ACs in UMi. Five of them were already known from N88, which we have confirmed. Four new ACs plus one AC candidate have been identified during this work. The variable stars are ordered by increasing number according to N88’s and our identifications. The magenta and yellow filled phase points mark stars within and beyond 12 times the galaxy half-light radius, respectively. The pulsation periods adopted to fold the light curves are from Gaia DR3 vari_rrlyrae table, except for (I) V178 whose light curve is folded with the period derived in our analysis of the time series data (see details in the text). Right panels: spatial distribution (top) and position on the CMD (bottom) of the 10 ACs (nine confirmed plus one candidate) with respect to the UMi members. The green filled circles mark V80 and V56, for which we do not confirm the N88 classification as ACs.