It still appears, according to the Espressif spec graceful shutdown should be part of Light-sleep, or Deep-sleep.

As I use microPython, would the equivalent of "esp_wifi_stop" be net.active(false) [where "net" is a user instance of a network object]?

BTW: I'm not actually using wifi connections, I ...

From the referenced document:
In Deep-sleep and Light-sleep modes, the wireless peripherals are powered down. Before entering Deep-sleep or Light-sleep modes, the application must disable Wi-Fi and Bluetooth using the appropriate calls (i.e., esp_bluedroid_disable(), esp_bt_controller_disable ...

According the the specification (see attached table image) current draw during light-sleep should max out at about 2ma. For this low current draw the wifi radio must be disabled. Does this occur as part of the light-sleep function call, or must the wifi radio be disabled prior to calling the light ...

I've used D1 Mini Pro modules and ESP-07 modules (in a programming fixture) both types with the same results. These modules are offered by many sellers, but there is no indication as to what company is the actual manufacturer.

I've also used numerous ESP versions (01S, 12E&F, 32) with a meandered ...

ESPNow is a communications protocol developed by Espressif to address long latency connection time of wifi.
I'm using ESP8266's & ESP32's with microPython; both using ESPNow communications. Using an ESP8266 as a sender doesn't require the ESPNow peer registration, however the ESP32 microPython does ...

My source is the controlled tests I ran comparing meandered inverted-F, half-wave dipole, and the ceramic chip antenna.

The ceramic chip antenna and dipole providing equivalent transmission distance performance. However, the ceramic chip antenna is less that 1cm. The meandered inverted-F does not ...

Controlled tests comparing a chip (ceramic) antenna to a basic wifi dipole with ESP8266 modules, demonstrated a commensurate transmission distance under varying weather conditions with the chip-antenna. The judged superiority of the ceramic antenna is do to the diminutive size of ceramic antenna as ...

Tom,

Richard is not having a "bottleneck" issue. As I understand it, the delay occurs every time his device re-connects to the wifi. Connections to wifi can take several seconds, and are also variable, as a function of distance from the router.

I had the same problem with remote sensors that ...

The first thing you'll need to do is create a Gateway using a single ESP32. The gateway receives ESP-Now from your sensors/devices (using the ESP32 AP interface), is connected to WiFi (using the ESP32 STA interface) and forwards the data to the MQTT broker. ESP-Now sending devices can request an ...

When you say it takes 7 seconds to re-connect that suggests you're using your wifi network for MQTT? While there are things that can be done to improve network connection time, it would be much better to use ESP-Now; reducing connection times from seconds to milliseconds. If you interested I can ...