overrides_J508_J538_J718_J721.der.pri for iPad Air (M2, 11-inch, Cellular), iPad Air (M2, 13-inch, Cellular), iPad Pro (M4, 11-inch, Cellular), iPad Pro (M4, 13-inch, Cellular); the release this version is read against has no modem package for them.
Header Dialect Qualcomm PRI Revision 0.1.161
Settings (10) All (10) efs:/nv/item_files/modem/mmode (2) efs:/nv/item_files/modem/nas (2) nv (3) pri (3) efs:/nv/item_files/modem/mmode (2) · SMS only = 1= On
Register for SMS onlyefs:/nv/item_files/modem/mmode/sms_only · UE usage setting = 1= Data centric
TS 24.301 UE usage settingefs:/nv/item_files/modem/mmode/ue_usage_setting efs:/nv/item_files/modem/nas (2) · hplmn_rat_order_ctrl unverified = 2
NAS setting: NAS mobility management / PLMN selectionefs:/nv/item_files/modem/nas/hplmn_rat_order_ctrl · HPLMN RAT order = LTE > WCDMA > GSM hex, 12 bytes
Home-PLMN RAT search order: uint16 count, then sys_sys_mode RATsefs:/nv/item_files/modem/nas/hplmn_rat_order nv (3) · Disable CM Call Type = 515
nv:5280 · PRI revision = 10551552= 0.1.161 0xa10100
Packed PRI Revision headernv:62005 · AAGPS Positioning Modes Supported = 1
nv:1920 pri (3) · Legacy NV item list = show list, 35 entries
Legacy NV items the modem may take from this file; with a value here: 1920, 5280, 62005.pri:nv-list · NV path schema index = show list, 318 entries
318 NV paths the PRI format knows (MAVZ); not overrides.pri:schema · pri:9fa710 = 178
Unidentified field, 1 time, 2 bytes: small binary blob that precedes the NV item list. 
iPad Air (M2, 11-inch, Cellular), iPad Air (M2, 13-inch, Cellular), iPad Pro (M4, 11-inch, Cellular), iPad Pro (M4, 13-inch, Cellular)