GitHub - parker-stephens/TMOHS1-Root-Utility: An interactive python script that enables root access on the T-Mobile (Wingtech) TMOHS1, as well as providing several useful utilites to change the configuration of the device.
An interactive python script that enables root access on the T-Mobile (Wingtech) TMOHS1, as well as providing several useful utilites to change the configuration of the device. - GitHub - parker-st...

Modifying All Outgoing TTL

Essentially masks all outgoing data as "on-device" rather than hotspot data. This will apply on each boot automatically.
echo "iptables -t mangle -I POSTROUTING -o rmnet_data+ -j TTL --ttl-set 64" > /etc/init.d/ttl.sh
echo "ip6tables -t mangle -I POSTROUTING -o rmnet_data+ -j HL --hl-set 64" >> /etc/init.d/ttl.sh
chmod 755 /etc/init.d/ttl.sh
ln -s /etc/init.d/ttl.sh /etc/rc5.d/S98ttl

Using Custom DNS Server(s)

Editing /etc/resolv.conf provides a temporary fix, but this file will be overwritten again on reboot, and even randomly while it's on. So let's make a script to defeat that!
Create /etc/init.d/customdns.sh with the contents:

#!/bin/sh

(while true
    do echo "nameserver 1.1.1.1" > /etc/resolv.conf
    sleep 15
done) &

This will make the script repeat every 15 seconds, ensuring that our DNS change sticks. You can replace 1.1.1.1 with whatever IPv4/6 server you want.
chmod 755 /etc/init.d/customdns.sh
ln -s /etc/init.d/customdns.sh /etc/rc5.d/S98customdns

Allowing More Devices On WiFi

By default the hotspot allows a maximum of 10 devices on a WiFi network, but we can change this to whatever we want. Edit the max_num_sta line in /data/configs/hostapd.conf for the 2.4GHz network or /data/configs/hostapd-wlan1.conf for the 5GHz network. There is also a file in /data/wlan_cfg/max_num, but this doesn't seem to do anything.

Changing USB Mode

At a shell:
ADB: /sbin/usb/compositions/9025
ADB + RNDIS + DIAG: /sbin/usb/compositions/902D
Default: /sbin/usb/compositions/9057

I've had trouble identifying whether or not this device has a MDM9207 or a MDM9607 (X5) modem, as the internal FCC photos show a MDM9207 modem and QPST also says MDM9207, but my hotspot's software references the MDM9607 several times, and considering I'm able to hit speeds of 75/15 (QCOM says the MDM9207 is only capable of 10/5), I'm just gonna assume it has the MDM9607 modem.

Considering that T-Mobile is literally handing these out for free with 30GB of data, I hope that eventually someone will figure out how to SIM unlock these devices. It appears as though there haven't been any software updates after ~January 2021 (device is on software version TMOHS1_0.04.18, and I'm able to find Google results about that version from around those times, but hell, it's possible it's even older than that).

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FCC ID 2APXW-TMOHS1 4G Mobile Broadband Router by Wingtech Group (Hong Kong) Limited
FCC ID application submitted by Wingtech Group (Hong Kong) Limited for 4G Mobile Broadband Router for FCC ID 2APXW-TMOHS1. Approved Frequencies, User Manuals, Photos, and Wireless Reports.

ati: (what the hell? i guess it's a MDM9607??)

Manufacturer: QUALCOMM INCORPORATED
Model: 4108
Revision: MPSS.JO.2.0.2.c1.7-00052-9607_GENNS_PACK-1  1  [Jul 17 2020 11:00:00]
SVN: 04
IMEI: ###############
+GCAP: +CGSM

OK

at+cgdcont=?

+CGDCONT: (1-24),"IP",,,(0-2),(0-4),(0-1),(0-1)
+CGDCONT: (1-24),"PPP",,,(0-2),(0-4),(0-1),(0-1)
+CGDCONT: (1-24),"IPV6",,,(0-2),(0-4),(0-1),(0-1)
+CGDCONT: (1-24),"IPV4V6",,,(0-2),(0-4),(0-1),(0-1)

OK