Glacial extent variability during last glacial period?
This map should address at least part of your question


The here documented GIS map and dataset contains a collection of Last
Glacial Maximum (LGM, ~21k yBP) paleoenvironmental data. It is the
first result of a project that aims to acquire, produce and publish
GIS datasets from non-GIS based sources such as analogous maps,
textual informations or figures of scientific publications for
prehistoric time slices. In combination with modelling results and
already available GIS-datasets related to the mentioned time frame, it
should enable other researchers and members from other projects to use
the maps in their work, properly cited and referenced. The map shows
LGM land ice sheets, paleo-stream networks and inland water in Europe,
a sea-level adapted (-120m) land mass and a Köppen-Geiger climate
classification derived from climate model data.

I know this is more broadly a field of active study and there is a relatively new method of analyzing cosmogenic nuclides to determine for what duration a surface has been exposed to cosmic radiation.
Broadly how this works is that surfaces exposed to cosmic radiation start to develop an isotopic signature, to the degree that you can tell how long a boulder has been exposed to the open sky (within a margin of error).
Joerg M. Schaefer of Lamont-Doherty Earth Observatory explains in Glacial Landscape (Cosmogenic Nuclide) in the Encyclopedia of Scientific Dating Methods:

High-sensitivity cosmogenic nuclide techniques applied to the moraine
record now afford for precise reconstruction of past glacier
fluctuations with centennial resolution and on a time scale ranging
from decades to beyond 100,000 years. It has been a long-standing
dream of geologists and climate scientists alike to precisely map land
ice change during the last ice age through the deglaciation period and
into the current interglacial, referred to as the Holocene.